TABLE 16.
PHENOTYPIC CORRELATIONS BETWEEN DOMAINS AT EACH AGE FOR ONE RANDOMLY SELECTED MEMBER OF EACH TWIN PAIR
| 1 | 2 | 3 | 4 | |
|---|---|---|---|---|
| 7 years | ||||
| 1. g | 1 | — | ||
| 2. NC English | .41** | 1 | — | |
| 3. NC mathematics | .39** | .74** | 1 | — |
| 9 years | ||||
| 1. g | 1 | |||
| 2. NC English | .40** | 1 | ||
| 3. NC mathematics | .41** | .74** | 1 | |
| 4. NC science | .37** | .74** | .75** | 1 |
| 10 years | ||||
| 1. g | 1 | |||
| 2. NC English | .41** | 1 | ||
| 3. NC mathematics | .38** | .76** | 1 | |
| 4. NC science | .37** | .78** | .77** | 1 |
| 7 years | ||||
| 1. g | 1 | — | — | |
| 2. TOWRE | .41** | 1 | — | — |
| 10 years | ||||
| 1. g | 1 | — | ||
| 2. PIAT | .55** | 1 | — | |
| 3. web mathematics | .61** | .50** | 1 | — |
Note.—NC, National Curriculum; TOWRE, Test of Word Reading Efficiency; PIAT, Peabody Individual Achievement Test.
**
Indicates significance at .01 alpha level.